A leading expert on elephant conservation has urged the government to step up security at a top-secret location housing a massive stockpile of elephant ivory. She cited fears it may be targeted by criminal syndicates looking to steal the lucrative contraband known as "white gold".

"It's always a concern having a stockpile in any location," said Grace Ge Gabriel, regional director for the International Fund for Animal Welfare, which has been tracking the illegal trade in ivory for more than a decade.

"Last year in Tanzania and Zambia, stockpiles were stolen. It's important to keep up security, because employees were implicated in both those ivory thefts - an indication of the level of corruption in these countries."

Gabriel said the chance of workers stealing ivory was much lower in Hong Kong, but it was still a worry, especially given recent huge hauls. More than 1,200 tusks weighing 3.8 tonnes were seized last October, one of the world's biggest finds since 2007.

Gabriel commended the city's customs officials, who along with Agriculture, Fisheries and Conservation Department staff, have increased their efforts to stop smugglers using Hong Kong as a transit point.

"But it puts an extra burden on Hong Kong's law enforcement in terms of storing the ivory," Gabriel said yesterday. In the past three months, more than six tonnes of elephant ivory worth close to HK$50 million was confiscated in Hong Kong.

At the same time, the wholesale price of ivory has tripled since 2006, alongside increased demand for the precious item at auction houses, according to a 2011 report by Gabriel's organisation on ivory markets in China.

Gabriel said there was only one option to ensure the ivory never fell into the wrong hands. "The best way to dispose of it after investigation is to destroy it by burning it, so that it is beyond use," she said, but this process could take years.

A spokeswoman for the department said the confiscated ivory was in "secure custody" at a classified location.

"We accord high priority to the security of confiscated items," she said.

Thousands of tusks as well as carved items are packed away in boxes under lock and key.

"Due to the high commercial value of the ivory, the storage premises are equipped with adequate security measures, including security guards and CCTV surveillance."

This article appeared in the South China Morning Post print edition as Ivory stash 'a tempting target'